Information signal transmission system and remote control device for the same

ABSTRACT

An information signal transmission system and a remote control device for such a system for allowing a viewer to continuously watch, for example, in a bedroom a program the viewer has watched in a living room. A recipient of information is detected referring to identification information set in a remote command device, and monitor devices are alternately switched for continuously providing the viewer with an information signal.

This is a Continuation of U.S. Ser. No. 08/977,591, filed on Nov. 25,1997, now U.S. Pat. No. 7,194,755, which is hereby incorporated byreference in its entirety herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an information signal transmissionsystem and a remote control device for the information signaltransmission system and finds applications in a system of video-handlingdevices that are interconnected using IEEE (the Institute of Electricaland Electronics Engineers) 1394, High Performance Serial Interface BusStandard (hereinafter simply referred to as IEEE1394). The presentinvention detects a recipient of information, and provides continuousinformation signal by switching devices in accordance with the recipientof information. For example, a program that has been enjoyed by a viewerin a living room may be continuously enjoyed by the viewer in a bed roomwith a simple operation. The present invention enhances ease of use inthis type of network.

2. Description of the Related Art

When a diversity of video-handling devices including a television tuner,a monitor device, and an optical disk device are arranged into anaudio-visual (AV) system, final output devices are typically arranged inthe center of the system with the remaining devices around them mutuallyconnected via dedicated lines.

More particularly, when the AV system is constructed of video-handlingdevices, video sources such as a television tuner and an optical diskdevice output a video signal and audio signal to a monitor device as afinal output device. The monitor device is thus provided with aplurality of video input terminals and a plurality of audio inputterminals, through which the video signal and audio signal are suppliedby the video and audio sources.

A video-handling device such as an optical disk device having arecording capability is connected to an output terminal of a monitordevice or directly to a video source such as a tuner to receive a videosignal and an audio signal. In such a connection, the video-handlingdevice transmits the video signal and audio signal over a shielded wireor a coaxial cable to reduce noise ingress.

In a camera-integrated VCR that processes a video signal in the form ofdigital signal, the input and output of the video signal and audiosignal are performed through an interface specified by IEEE1394Standard.

IEEE1394 Standard specifies high-speed, low-cost standard serialinterface.

Transmission of Signal

According to IEEE1394, two pairs of twisted pair lines are used totransmit signals. To send a signal in one direction, the two pairs areused in a half-duplex fashion. Data is transmitted on one pair while astrobe signal is transmitted on the other pair. By exclusively OR gatingboth signals, a receiver side reproduces a clock.

Three data rates of 98.304 Mbps (S100), 196.608 Mbps (S200), and 393.216Mbps (S400) are available and upward compatibility is assured in that adevice of one data rate specified works on any of data rates lower thanthe specified data rate.

Connection of Device

Each device has up to 26 ports, and has a maximum of 63 devicesconnected with ports fully used. Devices are flexibly connected as longas no loop connection is used and the number of connection stages is notgreater than 16.

According to IEEE1394, buses are initialized when the devices areconnected, and the devices are connected in a tree structure in whichone device is handled as a root device with the child and then grandchild devices connected under the root device. The addresses areautomatically assigned to the connected devices. In this way IEEE1394features a large flexibility in cable connection and setting involved inconnection is automatically performed.

1394 Communication

IEEE1394 allows a signal sent by one device to be relayed to anotherdevice so that the same signal is communicated to all devices within anetwork. More particularly, the network logically work as a buslikemanner though it is electrically connected in a point-to-point manner.For this reason, each device has to arbitrate the right to use the busprior to a start of transmission.

To get the right to use the bus, a device waits for the bus to beemptied and issues a request signal to its parent device. Upon receivingthe request signal, the parent device relays it to its own parent deviceand the request signal thus reaches the root device. The root devicereturns a permission signal in response to the request signal, and thedevice that receives the permission signal starts communication. When aplurality of devices concurrently issue request signals, all requestsexcept one are rejected.

Real Time Processing

In IEEE1394, a plurality of devices seeking the bus access right usesone bus on a time division multiplex basis. To transmit data, such as anaudio signal and video signal, which requires real time processing,communication should be guaranteed for a certain period of time toprevent data from missing.

Data requiring real time processing is handled through transmissionmethod called isochronous transmission. A node that manages thistransmission is selected during the initialization stage of the bus. Adevice that transmits in isochronous transmission is assigned necessaryband by the managing node. The root device transmits a cycle startpacket every 125 μs, and the band-assigned device transmits anisochronous packet in succession to the cycle start packet.

In this way the band-assigned device has the chance of transmissionevery 125 μs. When the overall capacity of the bands used in isochronoustransmission exceeds the bus capacity, band assignment cannot beperformed and isochronous transmission cannot be started.

In such an IEEE1394 interface, one bus is shared by a plurality ofdevices on a time-division multiplex basis, and the devices areconnected in a ring configuration or a star configuration to form anetwork. The video-handling devices are also configured in the same way.

Likewise, a network may be easily constructed in a single home. Forexample, a video signal reproduced by an optical disk device placed in aliving room may be viewed in a monitor device in a bed room.

It would be convenient if a user could continuously watch in the bedroom with an easy operation a program that has been viewed from theoptical disk device in the living room.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide aninformation signal transmission system that provides an informationsignal such as a continued video signal with devices switched, and aremote control device adapted to such an information signal transmissionsystem.

To achieve the above object, the information signal transmission systemof the present invention comprises recipient detecting means fordetecting a recipient of the information signal, wherein the informationsignal that has been supplied to the recipient by a first device iscontinuously supplied to the recipient by a second device, based on theresult detected by the recipient detecting means.

The recipient of the information signal is detected, and the informationsignal that has been supplied to the recipient by the first device iscontinuously supplied to the recipient by the second device, based onthe detected result by the recipient detecting means. Even when therecipient moves, the information provided by the first device iscontinuously provided by the second device.

The remote control device of an information signal transmission systemof the present invention transmits a remote control signal to which isadded an identification code identifying a recipient of the informationsignal.

The remote control signal to which is added the identification codeidentifying the recipient of the information signal is transmitted;thus, the operation of the entire system is smoothly switched byallowing to provide the information signal the device that receives theremote control signal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an audio-visual (AV) system of a firstembodiment of the present invention;

FIG. 2 is a diagram showing a packet for use in the AV system of FIG. 1;

FIG. 3 is a timing diagram illustrating the operation of the AV systemof FIG. 1;

FIG. 4 is a continuation of the timing diagram of FIG. 3;

FIG. 5 is a continuation of the timing diagram of FIG. 4;

FIG. 6 is a continuation of the timing diagram of FIG. 5;

FIG. 7 is a continuation of the timing diagram of FIG. 6;

FIG. 8 is a block diagram showing an AV system of a second embodiment ofthe present invention; and

FIG. 9 is a block diagram showing an AV system of another embodiment ofthe present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, the embodiments of the present invention arenow discussed.

First Embodiment

FIG. 1 is a block diagram showing an audio-visual (AV) system of a firstembodiment of the present invention.

The AV system comprises an optical disk device 2, and monitor devices 3Aand 3B which are connected through a bus BUS specified in IEEE1394 toform a network. The operation of the AV system 1 is switched byoperating a remote command device 4 or by directly operating eachdevice. The video signal and audio signal reproduced by the optical diskdevice 2 is monitored on the monitor device 3A in the same room as theoptical disk device 2 or on the monitor device 3B in another room.

In the optical disk device 2, a video reproducing block 6 under thecontrol of a control block 7 switches its operation to reproduce andoutput a video signal and audio signal from an optical disk. Under thecontrol of the control block 7, the video output block 8 switches itsoperation to code output data of the video reproducing block 6 andprovide its output to a network interface 9.

The control block 7, constructed of a microcomputer that controls theoptical disk device 2, switches the general operation of the opticaldisk device 2 in response to the operation of an unshown controlarranged on the optical disk device 2 or in response to a controlcommand input by a communication control block 10.

The network interface 9, constructed of input/output circuits forperforming communication process as specified in IEEE1394, communicateswith network interfaces of the devices connected to the bus BUS when thedevices are put to an idle state with the optical disk device 2connected to the bus BUS, and gets a device address for the optical diskdevice 2.

Each device address is constituted by a bus address for identifying eachbus connected in a bridge and a node address on each bus. Doubleaddressing for another device is precluded. In this network, buses areconnected in a bridge, and a video signal and audio signal are exchangedbetween buses, and for this reason each bus needs identifying by therespective bus address.

Through communications with other video-handling devices, the networkinterface 9 secures a device address that is assigned to none of theother devices, and holds the secured device address. The networkinterface 9 monitors the status of the bus BUS, and detects anydecoupling action in which any device is decoupled from the bus BUS.Based on the detected status, the network interface 9 newly performs adevice address detection process.

With the obtained device address as a reference, the network interface 9collects data output by the other video-handling devices constitutingthe network and then outputs it to the communication control block 10.The network interface 9 adds a device command output by thecommunication control block 10 to send to the other video-handlingdevices the data output by the communication control block 10 and thedata output by the video output block 8.

The AV system 1 is thus designed to transmit and receive a diversity ofdata in packet, and each packet includes, in its header portion, headerdata followed by an error correcting code for the header data as shownin FIG. 2. Next, a header for a data field comes in, followed by thedata field and then an error correcting code for the data field. When avideo signal, an audio signal, a control command or the like is sent toeach device, or when a device address is secured, these video signal,audio signal, control command or the like are assigned to the data fieldof each packet, and the device address of a destination is set in theheader of the data field.

The network interface 9 monitors the device address set in the header ofthe data field, and after collecting a packet designating the opticaldisk device 2, the network interface 9 error-correction processes thedata assigned to the data field and then outputs the corrected data tothe communication control block 10. In this way the network interface 9reports the control command and the device address of the destination tothe communication control block 10 based on the data assigned to thedata field. The network interface 9 assigns the video signal and audiosignal to the data field and sets the destination device address in theheader of the data field, and then sends the video signal and audiosignal to the device designated by the device address.

A memory 12 holds identification information ID1 of the recipient of theprogram of the optical disk. The identification information ID is ID1assigned by the remote command device 4, and in this embodiment, usershold their respective command devices. The memory 12 records which useris currently provided with the video signal and audio signal. The memory12 in an initial state records its default value.

A determining block 13 determines whether identification information ID2detected by a ID information detector block 14 matches theidentification information ID1 stored in the memory 12, and outputs theresult. The determining block 13 outputs a determination result of matchwhen the memory 12 stores the default value. The determining block 13thus determines whether the control command input from othervideo-handling device comes from the recipient of the program of theoptical disk.

The ID information detector block 14 detects and outputs identificationinformation ID1 and ID2 from the data input supplied from the networkinterface 9 to the communication control block 10.

The communication control block 10 analyzes the data of the data fieldsupplied via the network interface 9 and issues a control command to thecontrol block 7 as necessary. Through data communication with thecontrol block 7, the communication control block 10 sends a diversity ofdata via the network interface 9 as necessary.

More particularly, the communication control block 10 acquires the dataof the data field of a packet from the network interface 9 when thepacket designating the optical disk device 2 comes in. The communicationcontrol block 10 analyzes the data of the data field when thedetermining block 13 outputs a match as a result of determination. Whenthe data of the data field is a control command requesting areproduction operation of the optical disk device, the communicationcontrol block 10 compares attribute information set in the data fieldwith attribute information of the optical disk device 2 to determinewhether connection to a device requesting reproduction is possible.

The attribute information indicates attributes of each device. In caseof the optical disk device, the attribute information includes themanufacturer's name of the optical disk device 2, a type code indicativeof the type of each device (tuner, monitor device), a format of outputdata (MPEG 1(ISO/IEC 11172), MPEG2(ISO/IEC13818), MPEG4, G4, digitalaudio interface (IEC958) or the like). The communication control block10 determines whether connection to the device is possible bydetermining whether the output data format set in the attributeinformation matches its own format.

When it is determined that connection to the device is possible, thecommunication control block 10 sets the device address of the devicerequesting reproduction as a destination device address, issues aresponse control command, and then controls the control block 7 toreproduce from an optical disk, sets the same device address in thenetwork interface 9, and then sends a video signal and audio signalreproduced from the optical disk to the device requesting reproduction.

By repeating the above process steps, the communication control block 10reproduces from the optical disk or suspends the reproduction process,through data communication with the control block 7 in response to arequest from another device.

When the determining block 13 gives no match, the communication controlblock 10 ignores the control command input from another device. Toimprove ease of use, the optical disk device 2 modifies the recipient ofthe video signal and audio signal only when the remote command device 4to which the identification information ID1 registered in the memory 12is assigned is operated. When it is determined from the attributeinformation that connection to the device is difficult, thecommunication control block 10 notifies so the corresponding device.

Although the monitor devices 3A and 3B are identically constructed, bothhave different device addresses and are installed in different rooms.The monitor device 3A will be discussed mainly, and the common portiontherebetween will be discussed representatively in the discussion of themonitor device 3A.

In the monitor device 3A, a display 15 under the control of a controlblock 16 switches its operation, presenting a video signal input from avideo input block 17 and outputting an audio signal also input from thevideo input block 17. The video input block 17 under the control of thecontrol block 16 switches its operation, receiving the video signal andaudio signal from the bus BUS via a network interface 18. The videoinput block 17 further decodes the video signal and audio signal topresent them on the display 15. The monitor device 3A thus monitors thevideo signal and audio signal reproduced in the optical disk device 2.

A remote control receiver 20 receives a remote control signal sent bythe remote command device 4, and feeds the received result to thecontrol block 16, a communication control block 19 and an ID informationdetector block 21.

The control block 16, constructed of a microcomputer that controls theoperation of the monitor device 3A, controls the switching of thegeneral operation of the monitor device 3A in response to an unshowncontrol arranged on the monitor device 3A. The control block 16 detectsa control command assigned to the monitor device 3A from the receivedresult, and controls the general operation of the monitor device 3A forswitching according to the control command. The control block 16 alsoswitches the general operation of the monitor device 3A in response to acontrol command input from the communication control block 19.

Like the network interface 9 of the optical disk device 2, the networkinterface 18 acquires a device address. The network interface 18monitors the bus BUS, receives a packet assigned to the monitor device3A, and outputs data assigned to the data field of the packet to thecommunication control block 19 and video input block 17. The networkinterface 18 supplies to the video input block 17 the video signal andaudio signal that are destined to the monitor device 3A from the opticaldisk device 2, and acquires a control command issued to the monitordevice 3A from another device.

The network interface 18 under the control of the communication controlblock 19 issues the output data of the communication control block 19 toa device designated by the communication control block 19. In this way,the monitor device 3A issues the control command to another device.

An ID input control 22 comprises a plurality of control elementsarranged on the monitor device 3A, each element corresponding to itsrespective identification information ID. In the ID input control 22,the identification information ID by each control element is set tocorrespond to the identification information ID of the respective remotecommand device 4. In the monitor device 3A, unshown control elements areoperated after the ID input control 22 is selected, and the operation ofthe control elements is detected by the control block 16. The controlblock 16 reports the corresponding control command to the communicationcontrol block 19, which in turn adds the identification informationcorrespondingly to the control command.

The ID information detector block 21 detects the operation of the IDinput control 22 and reports the identification informationcorresponding to it to the communication control block 19. The IDinformation detector block 21 detects the identification informationadded to the remote control signal of the remote command device 4 fromthe result received by the remote control receiver 20, and outputs it tothe communication control block 19.

The communication control block 19 analyzes the control command inputvia the remote control receiver 20, and outputs the control command tothe network interface 18 based on the analysis result. The communicationcontrol block 19 adds the identification information detected by the IDinformation detector block 21, the attribute information and deviceaddress of the monitor device 3A, thereby issuing a control command.When a reproduction command of the optical disk device 2 is issued fromthe remote command device 4, for example, the communication controlblock 19 controls the control block 16 to feed main power to the monitordevice 3A, and adds the identification information, the attributeinformation and the device address to the reproduction command and thentransfers the resulting reproduction command to the optical disk device2. The identification information and attribute information are analyzedby the optical disk device 2. When a response command is received fromthe optical disk device 2, the video signal and audio signal the opticaldisk device 2 sends in succession are supplied to the user.

The monitor devices 3A and 3B constitute respectively a first and seconddevice, each of which provides the video signal and the audio signalconstituting information signal to the user.

The remote command device 4 holds its own assigned identificationinformation ID in an ID information holder block 26. A control block 27drives a transmitter block 29 in response to the operation of a control28, thereby transmitting a remote control signal to the monitor device3A, for example. The control block 27 adds the identificationinformation held by the ID information holder block 26 to the controlcommand borne by the remote control signal and then transmit them.

The remote command device 4 and the ID information detector block 14 ofthe optical disk device 2 constitute recipient detecting means fordetecting a recipient of the video signal and audio signal reproduced bythe optical disk device as video signal acquisition means, Furthermore,the ID input control 22 and the ID information detector block 14 of theoptical disk device 2 constitute the recipient detecting means fordetecting the recipient of the video signal and audio signal.

In the AV system 1 thus constructed (FIG. 1), the optical disk device 2and other devices are connected to the bus BUS and the system is poweredfor idling, and the network interfaces 9 and 18 interrogate the bus BUSfor, the device addresses of the devices connected thereto, and registerany device address, if unregistered in the bus BUS, to the respectivedevice. The network interfaces 9, 18 monitor the status of the bus BUS,and re-register the device addresses when the connection of the bus BUSis modified.

When a user switches the optical disk device 2 for power on bymanipulating a control on the remote command device 4 with the deviceaddress thus registered in step SP1 as shown in FIG. 3, the remotecommand device 4 goes to step SP2, where the remote command device 4adds the identification information to the corresponding control commandand transmits them as a remote control signal.

In step SP3, the remote control signal is received by the remote controlreceiver 20 of the monitor device 3A placed in the same room as theremote command device 4, and the identification information ID isdetected by the ID information detector block 21 connected to the remotecontrol receiver 20. With the optical disk device 2 switched for poweron, the control command borne by the remote control signal is acquiredby the communication control block 19. In step SP4, the communicationcontrol block 19 controls the control block 16 to switch the monitordevice 3A for main power on.

In step SP5, the identification information detected by the IDinformation detector block 21, the attribute information and deviceaddress of the monitor device 3A are added to the control command, andthese data are assigned to the data field, and the device address of theoptical disk device is assigned to the destination address before beingsent to the bus BUS. In this way the control command received by theremote control receiver 20 is transferred to the optical disk device 2.

In step SP6, the network interface 9 of the optical disk device 2acquires the packet to which the control command is assigned, and thecontrol command, the attribute information and the device addressassigned to the data field are input to the communication control block10. As shown in FIG. 4, the identification information ID out of thesedata is detected by the ID information detector block 14 in step SP7.

The determining block 13 determines in step SP8 whether theidentification information ID matches the identification informationstored in the memory 12. In the initial state, a match is obtainedaccording to the default value set in the memory 12. In step SP9, theidentification information ID1 is stored in the memory 12.

To determine whether the optical disk device 2 is connectable to themonitor device 3A, it is determined in step SP10 whether the attributeinformation of the monitor device 3A matches the attribute informationof the optical disk device 2. When it is determined that both areconnectable to each other, the response command is sent to the monitordevice 3A in step SP11.

The monitor device 3A receives the response command in step SP12, andthe optical disk device 2 notifies the monitor device 3A that the videosignal and audio signal will be transferred to the monitor device 3A. Instep SP13, the communication control block 10 controls the control block7 to switch the optical disk device 2 for main power on, and in stepSP14, the video reproducing block 6 starts reproduction of the opticaldisk.

Referring to FIG. 5, when the reproduction of the optical disk starts inthis way, the network interface 9 sends the reproduced video signal andaudio signal in step SP15, while the monitor device 3A starts receivingthe sent video signal and audio signal in step SP16 to present them onthe display 15.

With the reproduction of the optical disk starting, the user operates areserve control on the remote command device 4 in step SP17. In stepSP18, the remote command device 4 sends the control command to which theidentification information is added.

When the user is present in the same room where the monitor device 3A isplaced, the monitor device 3A receives the remote control signal in stepSP19. The device address and the attribute information are added to thecontrol command of the remote control signal in step SP20 and theresulting signal is sent to the optical disk device 2.

In step SP21, the control command is acquired by the communicationcontrol block 19 of the optical disk device 2, and is then input to thecommunication control block 10 of the optical disk device 2. The IDinformation detector block 14 detects the identification information ID2from the control command in step SP22.

The determining block 13 determines in step SP23 in FIG. 6 whether thedetected identification information ID2 matches the identificationinformation ID1 stored in the memory 12. When it is determined that bothmatch, the communication control block 10 issues a response command tothe monitor device 3A in step SP24, and the reproduction of the opticaldisk is temporarily suspended in step SP25.

In the AV system 1, once one individual starts the use of the system,the operation of the system is not interfered with by some one else, andthus the ease of use is accordingly assured.

The response command is fed to the communication control block 19 viathe network interface 18 of the monitor device 3A in step SP26, andcauses the monitor device 3A to be switched for main power off in stepSP27.

With the above setting, if the user goes to a bed room where the monitordevice 3B is placed and operates the remote command device 4 in stepSP28, the control command with the identification information added issent by the remote command device 4 in step SP29. The control command isreceived by the monitor device 3B in the bed room.

The monitor device 3B is switched for main power on by the control block16 in response to the control command in step SP31. The communicationcontrol block 19 adds to the control command the attribute informationand device address of the monitor device 3B and sends them to theoptical disk device 2 in step SP32.

The control command is acquired by the optical disk device 2 in stepSP33, and is then input to the communication control block 10 of theoptical disk device 2. The ID information detector block 14 detects theidentification information ID2 from the control command in step SP34.

The determining block 13 determines in step SP35 whether theidentification information ID2 matches the identification informationID1 stored in the memory 12. When a match is obtained, the communicationcontrol block 10 analyzes the attribute information of the controlcommand in step SP36 to determine whether the optical disk device 2 isconnectable to the monitor device 3B to which the control command istransferred.

When it is determined that both are connectable to each other, thecommunication control block 10 issues a response command to the monitordevice 3B in step SP37, and the response command is acquired by themonitor device 3B in step SP38. The optical disk device 2 notifies themonitor device 3B that the video signal and audio signal will betransferred to the monitor device 3B before the video signal and audiosignal are actually transferred in step SP39. When the signal transferstarts, the suspension of the optical disk is released.

The monitor device 3B starts receiving the video signal and audio signalin step SP40. In the AV system 1, the video signal and audio signalreproduced from the optical disk device 2 are continuously enjoyed withthe monitor device 3A switched to the monitor device 3B by the simpleoperation performed on the remote command device 4.

Instead the remote command device 4, the ID input controls 22 arrangedon the monitor devices 3A and 3B may be used. By operating the ID inputcontrols 22 for power on on the monitor devices 3A and 3B, for example,the control command with the identification information ID added isgenerated by the control block 16 and communication control block 19instead of the control command from the remote command device 4, and thegenerated control command is then transferred to the optical disk device2.

When the remote command device 4 is left and forgotten somewhere, the IDinput control 22 may be operated to allow the video signal and audiosignal reproduced from the optical disk device 2 to be switchably andcontinuously viewed on both the monitor devices 3A and 3B.

Receiving a reproduction end control command, the communication controlblock 10 of the optical disk device 2 determines that the supply of thevideo signal and audio signal to the destination device, to which thevideo signal and audio signal have been supplied, is completed and thecommunication control block 10 returns the content of the memory 12 toits default value. Another user is now permitted to use the system.

With the above arrangement, the identification information is assignedto the remote command device 4, and the video signal and audio signalfrom the optical disk device 2 are switchably supplied to the monitordevices 3A and 3B with the identification information as a reference. Bythe simple operation on the remote command device 4 carried, aparticular user continuously watches on the monitor device 3B the videosignal and audio signal that were provided on the monitor device 3A. Theuser thus enjoys the ease of use of the AV system 1.

Through the operation of the ID input controls 22 arranged on themonitor devices 3A and 3B, the control command with the identificationinformation added thereto is issued, and with the identificationinformation as a reference, the video signal and audio signal areswitchably supplied to the monitor devices 3A and 3B from the opticaldisk device 2. By the simple operation on the ID input controls 22, theparticular user continuously watches on the monitor device 3B the videosignal and audio signal that were provided on the monitor device 3A. Theuser again enjoys the ease of use of the AV system 1.

Second Embodiment

FIG. 8 is a block diagram showing an AV system of a second embodiment ofthe present invention.

The AV system 40 comprises an optical disk device 41, and monitordevices 42A and 42B which are connected through the bus BUS specified inIEEE1394 to form a network. The operation of the AV system 40 isswitched by operating a remote command device 43 or by directlyoperating each device. In FIG. 8, components identical to those in thefirst embodiment with reference to FIG. 1 are designated with the samereference numerals, and the description about them is not repeated.

In the AV system 40, the remote command device 43 comprises ID inputcontrols 44A, 44B, . . . , and in response of the operation of each ofthe ID input controls 44A, 44B, . . . , corresponding ID informationholder blocks 45A, 45B, . . . send identification information IDA, IDB,. . . The ID information holder blocks 45A, 45B, . . . are arranged intoa memory and register a plural pieces of identification information sothat the corresponding identification information is accessed by theoperation of the respective controls 44A, 44B, . . . .

When the control 28 is operated, a control block 46 adds, to the controlcommand corresponding to the control 28, the identification informationoutput by the ID information holder blocks 45A, 45B, . . . to generate aremote control signal, and outputs it via the transmitter block 29. Inthe AV system 40, the video signal and audio signal are continuouslyenjoyed on the monitor devices 42A and 42B, by the selection operationof the controls 44A, 44B, . . . without the need for carrying the remotecommand device 43.

In this embodiment, the optical disk device 41 is a simplified versionof the optical disk device 2 in the first embodiment, namely the opticaldisk device 2 without the ID information detector block 14, memory 12,and determining block 13. A communication control block 49 analyzes theattribute information of the control command input through the bus BUSto determine whether the connection to the device is possible. Afterissuing a response command, the communication control block 49 switchesthe operation of the optical disk device 41.

Each of the monitor devices 42A and 42B is provided with an IDinformation detector block 50, a memory 51, and a determining block 52.The determination of the information destination from the identificationinformation, performed by the optical disk device 2 in the firstembodiment, is performed by the monitor devices 42A and 42B in the AVsystem 40. Based on the determination result, the operation of theoptical disk device 2 is switched so that the reproduced signal that hasbeen monitored on the monitor device 42A is continuously monitored onthe monitor device 42B.

The ID information detector block 50 in the monitor device 42A has acombination of the ID information detector block 21 in the monitordevice 3A and the ID information detector block 14 in the optical diskdevice 2. More particularly, the ID information detector block 50detects identification information from the result received by theremote control receiver 20, and outputs it to a communication controlblock 54, and generates identification information in response to theoperation of the ID input control 22 and outputs it to a communicationcontrol block 54. The ID information detector block 50 detects theidentification information added to the control command acquired throughthe bus BUS.

The memory 51 holds the identification information, and the entireoperation is switched based on the identification information stored inthe memory 51 as a reference. The determining block 52 determines amatch by comparing the identification information stored in the memory51 with the identification information detected by the ID informationdetector block 50, and the determination result is output to thecommunication control block 54.

When the communication control block 54 receives a control command viathe bus BUS in the course of processing the video signal and audiosignal output by the optical disk device 41, the communication controlblock 54 switches the operation of the device in response to the controlcommand only when a match results from the determination process by thedetermining block 52. When a control command is input through the remotecontrol receiver 20 during the operation of the device, or when thecontrols are directly operated, the communication control block 54switches the operation of the device in response to the control commandor the operation of the controls only when a match results from thedetermination process by the determining block 52.

When a control command is input with main power down or when the controlis separately operated with main power down, the correspondingidentification information is registered in the memory 51, and theoperation of the device is switched in response to the control commandor the operation of the control.

In the AV system 40, the reproduction of the optical disk starts withthe monitor device 42A powered up, the operation of the monitor device42A is reserved on condition that the same identification information isinput, and the operation of the monitor device 42B is started so thatthe program that has been presented on the monitor device 42A iscontinuously presented on the monitor device 42B.

According to the arrangement shown in FIG. 8, the same advantage as thefirst embodiment will be offered if the single remote command device 43inputs selectively the identification information.

The same advantage as in the first embodiment will be offered event ifthe identification information is determined in the monitor devices 42Aand 42B instead of in the optical disk device 2.

Other Embodiments

In the above embodiments, each remote command device is assignedrespective identification number, or a single remote command device isused to selectively input a plural numbers of identificationinformation. The present invention is not limited to these embodiments.Identification information is registered in an IC card, and the IC cardis set in a remote command device or a video-handling device to add theidentification information to a diversity of control commands.

Instead of the IC card, a control command is generated based on theresult from a speech recognition and the identification information isadded to the control command as shown in FIG. 9. More particularly, aspeech recognition block 61 recognizes the voice of a user picked up bya microphone 62, and the speech recognition result is sent to a controlblock 63 in a remote control device 60. The control block 63 generates acontrol command based on the speech recognition result, and selects theidentification information of the user from a plural pieces ofidentification information stored in an ID information holder block 64.The control block 63 adds the identification information thus selectedto the, generated command, and sends them to a transmitter block 26.This arrangement offers the same effect as that of the precedingembodiments.

In the above embodiments, the operation of the optical disk device istemporarily suspended when the destination of the video signal and audiosignal is switched between the monitor devices. Alternatively, theprocess of temporary suspension is may be skipped.

In the above embodiments, the operation of one monitor device is forcedto stop before the other monitor device is activated when thedestination of the video signal and audio signal is switched between themonitor devices. Alternatively, the other monitor is operated to presentthe video signal and audio signal as necessary so that both monitordevices present an identical still image, and then the one monitordevice that has been viewed may be powered down. If the secondembodiment incorporates this method, the one monitor may be powered downunder the control of the other monitor device.

In the above embodiments, the monitor device that is continuously viewedis independently powered up. Alternatively, the monitor device that iscontinuously viewed is powered up under the control of the monitordevice that will be switched off, when switching is individuallyperformed on both monitor devices with the destination beforehand known.

In the above embodiments, the two monitor devices are alternatelyswitched on for presenting the video signal and audio signal output fromthe single optical disk device. The present invention finds applicationsnot only in such a system but also an AV system constructed of adiversity of devices. For example, a system may be constructed of aplurality of interconnected television receivers, each including a tunerand a monitor device. To continuously watch the same program with thetelevision receivers switched, data communications are required amongtelevision receivers in connection with information with identificationinformation as a reference, for example, about a receiver channel thathas been received.

In the above embodiments, the devices are interconnected using IEEE1394interface in the AV system that incorporates the present invention. Thepresent invention is not limited to such a system. The present inventionfinds applications in a system that may be constructed of compact diskplayer, amplifiers, loudspeakers using a diversity of serial interfacesor parallel interfaces, and further in a variety of wire or wirelesscommunication networks.

According to the present invention, the recipient of information isdetected referring to the identification information set in the remotecommand device, and the continued information signal is supplied to therecipient with the devices switched. With a simple operation, a user whowatched a program in a living room, for example, can continuously enjoyit in a bed room. The present invention thus offers improved ease of usein this type of network.

What is claimed is:
 1. An information signal transmission system,comprising: a network interface connected to a plurality of presentationdevices and a reproduction device through a network, wherein saidinformation signal transmission system provides an information signalreproduced by the reproduction device via one of the presentationdevices, and wherein each of the plurality of presentation devicescomprises a remote control receiver, wherein said remote controlreceiver is operable to receive a remote control signal sent by a remotecontrol device, wherein the remote control signal comprisesidentification data; a destination object detecting module for detectinga destination object by detecting the identification data associatedwith a control request in conjunction with controlling the reproductiondevice, wherein said identification data is used for identifying adestination object of said information signal; a storage module forstoring the identification data; a determination module for determiningthe identification data detected by the destination object detectingmodule and the identification data stored by the storage module; acontrol module for controlling output of the information signal via oneof the plurality of presentation devices as a function of theidentification data, wherein, when the identification data of the remotecontrol signal is detected and a different destination object isidentified, reproduction of the reproduction device is suspended, theoutput of the information signal is switched to a second of theplurality of presentation devices, and suspension of the correspondingreproduction device is released.
 2. The information signal transmissionsystem of claim 1, wherein, when said control module receives a reserverequest from one of said plurality of presentation devices through saidnetwork interface and said reserve request includes identification dataindicating said identification code identifying a user, and when saidcontrol module receives said pause command indicating said firstpresentation device, said control module terminates outputting saidinformation signal to said first presentation device through saidnetwork interface, such that an information signal module outputs saidinformation signal to a second presentation device from the point insaid information signal when said control module stopped outputting saidinformation signal to said first presentation device.
 3. The informationsignal transmission system of claim 1, wherein in response to a controlrequest received via the presentation device except of one of thepresentation devices if the determine component determines that theidentification data detected by said destination object detectingcomponent matches the identification data stored by said storecomponent.
 4. The information signal transmission system of claim 1,wherein an identification module determines that the identification codeof said identification module in said reserve request matches theidentification code of said identification data stored by saididentification module and sends a pause command to said control module,said pause command indicating a first presentation device.
 5. A methodof transmitting an information signal, comprising: connecting aplurality of presentation devices to a reproduction device through anetwork, and wherein each of the plurality of presentation devicescomprises a remote control receiver, wherein said remote controlreceiver is operable to receive a remote control signal sent by a remotecontrol device, wherein the remote control signal comprisesidentification data, providing an information signal reproduced by thereproduction device via one of the plurality of said presentationdevices; detecting a destination object by detecting the identificationdata associated with a control request in conjunction with controllingsaid reproduction device, wherein said identification data is used toidentify a destination object of said information signal; storing theidentification data; determining the identification data detected by thedestination object detecting step and the identification data stored insaid storing step; controlling output of the information signal, whereinthe controlling step controls the storing step to store theidentification data and to output the information signal via thepresentation device related to a control request; detecting theidentification data; wherein the controlling step outputs theinformation signal via the presentation device as a function of theidentification data, wherein, when the identification data of the remotecontrol signal is detected and a different destination object isidentified, reproduction of the reproduction device is suspended, theoutput of the information signal is switched to a second of theplurality of presentation devices, and suspension of the correspondingreproduction device is released.
 6. The method of transmitting aninformation signal of claim 5, wherein, when said control step receivesa reserve request from one of said plurality of presentation devicesthrough said network interface and said reserve request includesidentification data indicating said identification code identifying saiduser, an identification step determines that the identification code ofsaid identification data in said reserve request matches theidentification code of said identification data stored by saididentification step and sends a pause command to said control step, saidpause command indicating said first presentation device, and when saidcontrol step receives said pause command indicating said firstpresentation device, said control step causes an information signaloutputting step to stop outputting said information signal to said firstpresentation device through said network interface, such that saidinformation signal outputting step begins to output said informationsignal to a second presentation device from a point in said informationsignal when said control step stopped outputting said information signalto said the presentation device.
 7. A method of displaying aninformation signal on different destination display devices connected ina network, comprising: storing identification data used to identify adestination display device of said information signal; outputting aninformation signal to a first destination display device via saidnetwork; receiving a control request from a second destination displaydevice through said network, said control request includingidentification data; comparing the identification data in said controlrequest with said stored identification data to detect a match; andsuspending the outputting of said information signal to said firstdestination display device and releasing the outputting of saidinformation signal to said second destination display device via saidnetwork if a match is detected; wherein said first destination displaydevice and said second destination display device each includes acontrol block and a control receiver operable to receive a controlsignal generated by a user-activated operation and to feed a result ofsaid received control signal to said control block.
 8. The method ofclaim 7, wherein said supply of said information signal to said firstdestination display device is terminated after said information signalhas been supplied to said second destination display device.
 9. Themethod of claim 7, wherein said supply of said information signal tosaid first destination display device is terminated after said controlrequest has been received from said second destination display device.10. The method of claim 7, further comprising determining if said seconddestination display device is operable to display said informationsignal and then, if it is determined that said second destinationdisplay device is operable to display said information signal, supplyingsaid information signal to said second destination display device. 11.The method of claim 7, wherein said identification data is generated bycircuitry in said second destination display device.
 12. The method ofclaim 7, wherein said first and second destination display devices arelocated in different rooms in a house.
 13. The method of claim 7,wherein said information signal is provided by a source of audio/videocontent.
 14. Apparatus for displaying content on different destinationdisplay devices connected in a network, comprising: a memory configuredto store identification data used to identify a destination displaydevice of said information signal; a content source configured to outputcontent to a first destination display device via said network; areceiver configured to receive a request from a second destinationdisplay device through said network, said request includingidentification data; a comparator configured to compare theidentification data in said request with said stored identification datato detect a match; said content source suspending the supply of saidcontent to said first destination display device and releasing saidcontent to said second destination display device via said network if amatch is detected; wherein said first destination display device andsaid second destination display device each includes a control block anda control receiver operable to receive a control signal generated by auser-activated operation and to feed a result of said received controlsignal to said control block.
 15. The apparatus of claim 14, whereinsaid supply of said content to said first destination display device isterminated after said content has been supplied to said seconddestination display device.
 16. The apparatus of claim 14, wherein saidsupply of said content to said first destination display device isterminated after said request has been received from said seconddestination display device.
 17. The apparatus of claim 14, wherein saidcontent source includes a control block configured to determine if saidsecond destination display device is operable to display said contentand then, if it is determined that said second destination displaydevice is operable to display said content, said content source suppliessaid content to said second destination display device.
 18. Theapparatus of claim 14, wherein said second destination display deviceincludes circuitry to generate the identification data.
 19. Theapparatus of claim 14, wherein said first and second destination displaydevices are located in different rooms in a house.
 20. The apparatus ofclaim 14, wherein said content is audio/video content.
 21. A method ofchanging over the display of content supplied to a first destinationdisplay device connected in a network to display said content on asecond destination display device connected in the network, comprising:transmitting from said second destination display device to saidnetwork, a control request including identification data used toidentify the second destination display device of said content fordetermining if said second destination display device is permitted todisplay said content; and suspending the supply of said content to saidfirst destination display device and releasing the supply of saidcontent from said network to said second destination display device ifsaid second destination display device is permitted to display saidcontent; wherein said second destination display device includes acontrol block and a control receiver operable to receive a controlsignal generated by a user-activated operation and to feed a result ofsaid received control signal to said control block; and whereby thedisplay of said content is changed over from said first destinationdisplay device that had been displaying said content up until the timesaid control request is transmitted from said second destination displaydevice.
 22. The method of claim 21, wherein said identification data isgenerated by circuitry in said second display device.
 23. The method ofclaim 21, wherein said second destination display device and said firstdestination display device are located in different rooms in a house.24. The method of claim 21, wherein said content is provided by a sourceof audio/video content.
 25. A first destination display device connectedto a network for displaying content that is being supplied to anddisplayed on a second destination display device, comprising: atransmitter configured to transmit to said network a request includingidentification data used to identify the first destination displaydevice of said content for use in determining if said first destinationdisplay device is permitted to display said content; and a receiverconfigured to receive said content from said network if said firstdestination display device is permitted to display said content; whereinsaid first destination display device includes a control block and acontrol receiver operable to receive a control signal generated by auser-activated operation and to feed a result of said received controlsignal to said control block; and whereby the display of said content onsaid second destination device is suspended to change over the displayof said content from said second destination display device that hadbeen displaying said content up until the time said control request istransmitted from said first destination display device, and the displayof said content is released to said first destination display device.26. The apparatus of claim 25, wherein said supply of said content tosaid second destination display device is terminated after said contenthas been supplied to said first destination display device.
 27. Theapparatus of claim 25, wherein said first destination display deviceincludes circuitry to generate said identification data.
 28. Theapparatus of claim 25, wherein said first destination display device andsaid second destination display device are located in different rooms ina house.
 29. The apparatus of claim 25, wherein said content isaudio/video content.